Bit for rotary tube cleaners



March 3,1953 v, H, AKER 2,629,887

BIT FOR ROTARY TUBE CLEANERS Filed 'Obt. '26, 1949 GHorneq Patented Mar.3, 1953 BIT FOR ROTARY TUBE CLEANERS Virgil H. Baker, Springfield, Ohio,assignor to Elliott Company, Pittsburgh, Pa., a corporation ofPennsylvania Application. October 26, 1949, Serial No. 123,720

'7 Claims. (Cl. -10413) This invention relates to tube cleaner bits ofthe kind which are motor driven through tubes to remove scale andencrustationsv from the inner tube wall. Such bits ordinarily comprise.a rotatable body, and a plurality of sets of cutter elements carried bythe head for radial movement outward under the influence of centrifugalforce.

The instant invention contemplates a reorganization and design of themounting for the cutter elements.

Thus, the object of the invention is to simplify the construction aswell as the means and mode of operation of tube cleaner bits asdisclosed herein, whereby such bits may not only be economicallymanufactured, but will be more efficient and satisfactory in use,adaptable for use in tubes of various diameters (within certain limits),having relatively few parts and be unlikely to get out of repair.

A further object is to allow a'greater than usual radial movement ofthe. cutter elements to enable the bit to deal more effectively withheavy encrustations and to make. it applicable to openings of varyingdiameter.

Another object of the invention is to simplify assembly of the bit andto improve its operationtional characteristics by providing forindependent support in the body of cutter pin mounting blocks.

A further object of. the invention is to define longitudinal as well asradial limits. of. motionfor the blocks.

A further object of the invention. is to provide a machine possessingthe advantageous structural features, the inherent meritoriouscharacteristics and the mode of operation herein mentioned.

With the above'primary and other incidental.

objects in view as will. more fully appear in the specification, theinvention intended to be'protected by Letters Patent consists of thefeatures of construction, the parts and combinations cleaner bit inaccordance with the present.

invention;

Fig. 2 is a front end view of the. bit of Fig. 1;

Fig. 3 is a view similar to Fig. lwith. the cutters removed and showingthe-manner of assem- 2 bly and. mode of installation of the mountingblocks;

Fig. 4 is a view in. cross section taken substantially along the line4-4 of Fig. 1;

Fig. 5 is a view in cross section taken. substantially along the line5-5 of Fig. 1;

Figs. 6 and 7 are detail views of the mounting. block in the forward endof the bit; and

Figs. 8 and 9 the detail views of the mounting block in the rearward endof the bit.

Like parts are indicated by similar characters of reference throughoutthe several views.

Referring to the drawing, in the illustrative embodiment of theinvention a tube cleaner bit comprises an integral body H of cast ormachined construction having an axially extending threaded extension 12used to secure the bit to a motor shaft.

The bit is provided with three sets of cutter elements so disposed as tomove outward under the influence of centrifugal force when the bit isrotated, the outward motion of the cutter elements being limited by theinternal wall of the tube being cleaned or by stops incorporated intheir mounting. Each set of cutter elements being identical in itsconstruction and mounting, only one will be described.

A set of cutter elements is made up of a pair of disc cutters l3 and I4and a cone cutter IS, the latter being in advance of the others withrespect to the front or working end of the bit. The cutter assembly isrecessed in a chamber Hi in the body I I and projects a greater orlesser distance beyond the periphery of the body in accordance with thespeed of rotation of the bit and the extent of radial movement permittedwithin the tube. Centrally disposed openings in the cutters permitpassage of a pin ll therethrough, the opposite. ends of the pin i! beingreceived in mounting blocks l8 and i9 which are in turn installed inrecesses. 2| and, 22 formed in the body ll, respectively rearwardly ofand in advance of the chamber [6.

Th block l8, shown in detail in Figs. 8 and 9, is generally rectangularin shape, the broad sides 23. thereof being fiat. The narrow sides 24thereof are arcuate and at the bases of the sides 24 are arcuate flanges25. Extending transversely through the broad sides of the block is anelongated opening 20 to receive one end of the pin [1.

The recess 2! receiving the block it is produced by a longitudinallymilled slot 26, a radial bore 21 opening through the front end of theslot 26 and a counterbore 28 at. the. rear of slot 26. The. counterbore23 is formed by a milling operation after formation of the slot 26 andbore 21.

There is a complementary relation between the flat sides 23 of block l8and slot 28, which is utilized in inserting the block in recess 2| and acomplementary relation of arcuate sides 24 and flanges 25 of the blockto bore 21 and counterbore 28 of the recess, utilized to restrictlongitudinal motion of the block. It is first inserted in recess 2| withthe flat sides 23 parallel to the slides of slot 26. Then it is turned adistance of about ninety degrees to move arcuate sides 24 into bore 2'!and flanges 25 into counterbore 28. At the same time opening 20 isbrought into position overlying or in registry with the forward recess22.

In connection with the configuration of block l8 and recess 2| it is tobe noted that the thickness of flanges 25 with respect to the depth ofcounterbore 28 is such as to permit a substantial amount of radialmovement of the block. The limit of such motion is defined by a shoulder29 formed at the juncture of bore 2'! and counterbore 28 and engageableby flanges 25. Further, the transverse cutter pin opening 20 in block I8is elongated in a radial direction. Pin 20 thus is permitted asubstantial radial movement relatively to the block.

The construction of forward block l9 and the formation of its recess 22are the same as those of block l8 and recess 2| except that a greaterrestriction is imposed upon radial movements of the block |9 and theadjacent end of its cutter pin. As shown in Figs. 6 and '7, the block l9has opposed flat sides 3|, opposed arcuate surfaces 32, flanges 33 and aslightly elongated opening 34. Recess 22 has a slot 35, bore 36 andcounterbore 31, the various formations of the recess and blockcooperating in the same manner described in connection with block I8 andrecess 2|. In this instance, however, flanges 33 are relatively broad orthick and counterbore 31 is relatively shallow so that the extent ofradial motion permitted block |9 is materially less than that permittedblock I8. Further, opening 34 in block I9 is nearly cylindrical so thatthe end of pin received in the block has less freedom of radial motionthan the opposite end received in block IS.

The described construction and arrangement of the cutter mounting, withreference to the relative radial motion permitted the blocks and thecutter pin, is such as to accentuate the relationship between the conecutter i and the disc cutters l3 and I4. Thus, the front end of thecutter assembly is relatively confined and tends to bore into the cruston the tube wall, while the rearward end expands toward contact with thetube wall and cuts away the crust.

In the assembly of the parts, the blocks l8 and I9 are first installedin their respective recesses 2| and 22 where they are suspended againstaxial dislodgment by reason of their complementary fit in respectivebores 21 and 36. Cutters [3, l4 and I5 are stacked between the blocks,and pin I! is then inserted into opening 20 in block l8 and allowed todrop through the registering openings in the cutters and into opening 34in block I9. A head 38 on pin limits inward motion of the pin andfacilitates withdrawal thereof.

The slot 26 opens through the inner or rearward end of the body II forsimplified assembly,

of parts. A disc 39 overlies the slot 26 and prevents inadvertentwithdrawal of the pin it being contemplated that the disc 39 should be-4 held in place by a nut screwed down over the projection l2.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desirable, but whichobviously is susceptible of modification in its form, proportions,detail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprise but one of several modes of putting the invention into efiect.

Having thus described my invention, I claim:

1. A tube cleaner bit, including a body, longitudinally spaced openingsin said body to receive cutter mounting blocks, each of said openingscomprising a longitudinal slot, a radial bore opening at its outer endthrough the top of said slot and an arcuate counterbore at the bottom ofsaid slot, substantially rectangular blocks received in said openings,said blocks including flanges on their inner ends and on opposite sidesthereof to lie in said counterbores, longitudinal openings in saidblocks, a pin extending between said blocks and having its ends receivedin said openings therein, and cutter means on said pin.

2. A tube cleaner bit according to claim 1, characterized in that thecounterbore in one of the openings in said body is radially elongatedwith respect to the other.

3. A tube cleaner bit according to claim 1, characterized in that theopening in one block is radially elongated with respect to thecorresponding opening in the other block.

4. A tube cleaner bit, including a body, longitudinally spaced openingsin said body to receive cutter mounting blocks, each said openingscomprising a rectangular slot, a radial bore opening at its outer endthrough the front of said slot and a counterbore at the rear of saidslot, a substantially rectangular block to be received in each saidopenings with a loose fit, said block having opposed arcuate sidescomplementary to the shape of said bore for restricted longitudinalmovement of the block, and flanges at the bases of said arcuate sidescomplementary to the shape of said counterbore, the distance radially ofthe body of said counterbore exceeding the thickness of said flanges topermit limited radial movement of the block, and cutter means supportedbetween said blocks.

5. A tube cleaner bit according to claim 4, characterized in that theother opposed sides of each said blocks are flat and spaced apart adistance not greater than the width of the slot at corresponding points,the blocks being inserted in said openings with said flat sides parallelto the sides of said slot and then turned through an arc of about ninetydegrees to bring said flat sides at right angles to the sides of theslot.

6. A tube cleaner bit wherein cutter means is supported on a bodybetween mounting blocks having limited radial movement relative to thebody, characterized by longitudinally spaced openings in the body toreceive said blocks, each of said openings comprising a longitudinalslot, a radial bore opening through the radially outward end of saidslot and a counterbore at the 5 radially inward end of said slot, saidblocks having portions complementary to said bore and said counterborebut undersize with respect thereto whereby to be supported in theopenings and to have limited radial movement therein.

7. A tube cleaner bit, including a rotatable body, a pair of generallyrectangular blocks presenting opposed flat sides, opposed arcuate sidesand arcuate flanges at the bases of said arcuate sides, longitudinallyspaced recesses for said blocks in said body, each of said recessesincluding a rectangular 5101; having a width slightly greater than thedistance between the flat sides of said blocks, a bore and a counterboretransversely formed in said slot, said slot having a complementaryrelation to the flat sides of a block for insertion of the block intothe recess, said bore and counterbore achieving a complementary relationto the arcuate sides and the flanges on said blocks respectively inresponse to a ninety degree turn of the block after insertion into therecess, and cutter means supported between said blocks.

VIRGIL H. BAKER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

